Objective : The present study investigates patterns of consumption of alcohol, cigarettes, and over the counter drugs (OTC) in Korean patients with PTSD and psychiatric patient controls and healthy controls from multicenter hospital samples. Method : Data were collected from 18 hospitals nationwide. Patients with PTSD were compared with nonpsychotic psychiatric disorders control and healthy control subjects on psychometric measures of consumption of alcohol, cigarettes, and OTC drugs. Result : Ninety-three patients with PTSD, 73 patients with psychiatric disorders control, and 88 healthy control subjects were enrolled. There were significant differences in the frequency of alcohol drinking among the three groups ($X^2$=12.93, df=6, p=0.044). Only 3.2% of healthy control subjects drank alcohol more than 4 times a week, but 43.9% of PTSD group and 46.5% of mental disorder controls drank alcohol more than 4 times a week, respectively. Regarding cigarette smoking, there were no differences among the three groups. There were significant differences in uses of OTC drugs among the three groups; 16.7 % in the PTSD group, 14.9% in the psychiatric control group and 1.3% in the heath control group, respectively ($X^2$=11.31, df=2, p=0.004). Conclusion : In this study, patients with PTSD showed significant differences in the frequency of consumption of alcohol and OTC drugs, as compared with healthy controls. However, there were no differences between the PTSD and psychiatric patient control groups. Since all subjects were enrolled from hospital based sample, results may differ in the community samples. Further studies will be needed for the evaluation of substance uses in these groups.